Measuring distance, perimeter and area on a PDF
Measure distances, perimeters and areas on drawings and plans in PDF by Zaweba, with a drawing scale, calibration and snapping to ends and crossings.
Plans, drawings and maps carry measurements that are not written down. The width of a room, the length of a fence, the area of a floor to be tiled. On paper you would reach for a scale rule. In PDF by Zaweba, you use Comment > Measure.
It gives distance, perimeter and area, with a drawing scale, calibration and snapping to ends, middles, crossings and lines. A Measuring panel lists the measurements, which can be exported, and they are real measurement annotations that other programs read.
The three measurements
Distance measures a straight line between two points: a wall, a doorway, a gap between two parts.
Perimeter measures the total length round a shape: a fence line, a skirting board, the edge of a garden bed.
Area measures the space inside a shape: a floor to carpet, a roof to cover, a plot of land.
Setting the scale
A drawing is smaller than the thing it shows, so measurements need a scale. If you know the drawing's scale, such as one to fifty, set it, and measurements come out in real-world units.
Calibration is the other way and often the safer one. Find something on the drawing whose real length you know, such as a dimensioned wall or a scale bar, measure it and tell the app its true length. Every measurement after that uses the same ratio. Calibration protects you from drawings that have been resized, printed to a different paper size or scanned slightly off, because it works from the drawing as it now is.
Snapping for precision
Clicking exactly on the end of a line is hard. Snapping helps by pulling your point onto ends, middles, crossings and lines in the drawing. Measuring wall to wall becomes a matter of getting close and letting the point snap into place.
Zooming in helps too. The closer you are, the more precisely you can pick the right line when several run close together.
The Measuring panel
Every measurement is listed in the Measuring panel. That gives you a running record of what you have measured, which you can check and export. Exporting suits estimating jobs, where measurements feed a quote or a materials list.
Because the measurements are real measurement annotations, other PDF programs that understand them can read them too. Send the PDF to someone else and they see the same measurements.
Who measures from a PDF
Builders and tradespeople take measurements from plans for quotes. Homeowners check room sizes on estate agent floor plans before buying furniture. Students and engineers check dimensions on technical drawings, and gardeners work out the area of a lawn from a site plan.
Checking the scale twice
Always calibrate or check the scale first, and test it on a second known dimension. If both come out right, you can trust the rest.
Be wary of drawings marked "not to scale". Calibration still gives you numbers, but the drawing itself may not be accurate enough to trust them.
Remember that measurements are comments. They appear with other comments and can be filtered, and flattened if you want them fixed into the page.
With scale, calibration and snapping, measuring in PDF by Zaweba turns any drawing into something you can take real figures from, offline and without a scale rule.
